异形截面孔磨粒流精密加工质量分析

Quality Analysis for Abrasive Flow Precision Machining of Special-shaped Holes

采用磨粒流精密加工技术对异形截面深孔进行数值模拟及实验研究,通过大涡模拟方法对钛合金异形截面孔零件进行数值分析,并进行相关实验研究以揭示磨粒流抛光异形曲面的表面创成机理。磨粒流精密加工数值分析揭示了磨粒流动态压力、速度、磨粒对壁面压力和壁面剪切力对壁面作用规律,获得了异形截面孔内流向截面的漩涡位置分布与漩涡产生原因以及漩涡与磨粒相互作用关系。经过磨粒流精密加工后,异形曲面的表面粗糙度由Ra=7.136μm、Rz=40.103μm减小到Ra=1.822μm、Rz=8.964μm,异形截面孔内表面凸起、球化现象去除,表面质量明显改善,漩涡使异形曲面的表面质量得到大幅改善。

The abrasive flow precision machining technology was used to carry out numerical simulation and experimental research for the special-shaped deep holes.A large-eddy simulation method was used to numerically analyze the titanium alloy shaped hole parts,and related experimental studies were conducted to reveal the creation mechanism of the surface of the abrasive flow machining special-shaped curved surfaces.The study finds that:the effects of dynamic pressure,velocity,the pressure of abrasive particles on wall surfaces and the effects wall shear force on wall surfaces were revealed through numerical analysis of precision machining of abrasive flow.The vortex position distribution and the cause of the vortex as well as the interaction relationship between the vortex and the abrasive particles in the flow directional sections of the special-shaped section holes were obtained;After precision machining by abrasive flow,the surface roughness of special-shaped curved surfaces improves from Ra=7.136μm,Rz=40.103μm to Ra=1.822μm,Rz=8.964μm respectively.The protrusions and spheroidization on the inner surfaces of the shaped holes are removed,and the surface quality is significantly improved.The vortex greatly improves the surface quality of the special-shaped curved surfaces.